Cover film for testing, testing member including cover film, and method of manufacturing cover film for testing

ABSTRACT

The cover film for testing comprises a base material, a hydrophilic coating layer laminated on a surface of the base material, and an adhesive layer partially laminated on a surface of the hydrophilic coating layer opposite to the base material, whereby the cover film for testing has a region in which the adhesive layer is absent and the hydrophilic coating layer is exposed.

CROSS REFERENCE TO RELATED APPLICATION

This application is based on and incorporates herein by referenceJapanese Patent Application No. 2017-076699 filed on Apr. 7, 2017.

TECHNICAL FIELD

The present invention relates to a testing member used for opticallytesting a specimen, a cover film for testing used therein, and a methodof manufacturing the cover film for testing.

BACKGROUND ART

A method of optically testing a specimen exists for the purposes ofmeasuring the turbidity of a specimen such as liquid and measuring theamount of a specific component in the specimen, etc. In such an opticaltesting method, the specimen is irradiated with light to measure lightthat is caused by the irradiation. More specific examples of such atesting method include a method of irradiating a specimen with light andmeasuring the degree of scattering of the light, a method of measuringan amount of absorption of light by a component in a specimen when thespecimen is irradiated with light and the light transmits through thespecimen, and a method of measuring fluorescence generated in aspecimen. In such a testing method, conventionally, the specimen hasbeen stored in a test tube or cell having an appropriate volume, such asseveral milliliters.

In recent years, a testing method has been developed which uses atesting member provided with a fine groove for storing a specimen, assubstitute for the above test tube or cell. In such a method, the testis possible even for a small amount of the specimen and thus requiresonly a slight amount of the specimen. Moreover, the use of a testingmember having a plurality of grooves enables collective measurement anda number of specimens can therefore be tested at the same time.

Patent Literature 1 discloses a multi-layered composite structure as anexample of the above-described testing member having fine grooves. Themulti-layered composite structure comprises a base material thatconstitutes side surfaces of the grooves, a first layer that constitutesbottom surfaces of the grooves, and a resealable film as a cover thatcovers the grooves (paragraph 0032 and FIG. 2 of Patent Literature 1).Patent Literature 2 discloses a plastic microchip in which a plasticsubstrate that has a fine flow channel as the above groove at thesurface and a plastic film as a cover that covers the groove are bondedtogether via an adhesive (claim 1 of Patent Literature 2).

PRIOR ART LITERATURE Patent Literature

[Patent Literature 1] Japanese Translation of PCT InternationalApplication, No. 2006-510384

[Patent Literature 2] JP2008-157644A

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

As installed in the testing members described in Patent Literature 1 andPatent Literature 2, the grooves may be covered by a cover to preventtroubles, such as vaporization and leakage of specimens and pollution ofspecimens. Such a cover has to be well fixed to the substrate in orderto prevent its delamination and dropping from the substrate providedwith the grooves. Such a cover may therefore be fixed to the substrateusing an adhesive or a pressure sensitive adhesive. For example, inPatent Literature 2, the plastic film is adhered using an adhesive tothe surface of the plastic substrate having the fine flow channel.

In the conventional fixing method as disclosed in Patent Literature 2,however, the adhesive or pressure sensitive adhesive used may invadeinto the groove of the substrate and/or fill the groove. In this case,the test cannot be well performed because the specimen cannot besufficiently stored in the groove.

In addition, the testing member in which the grooves are covered by acover as described above requires costly and complex means for storingspecimens in the grooves. For example, in the testing member disclosedin Patent Literature 1, the testing member is rotated to generatecentrifugal force, which is utilized to store the specimens at certainpositions of the grooves (paragraph 0033 of Patent Literature 1). In thetesting member disclosed in Patent Literature 2, the specimen is sent tothe groove using a pump (paragraph 0031 of Patent Literature 2). Thus, atesting member is needed with which a specimen can be easily stored in agroove without using such costly and complex means.

The present invention has been made in consideration of such actualcircumstances and an object of the present invention is to provide acover film for testing which can be well fixed to a substrate having agroove and with which a material that constitutes an adhesive layer doesnot invade into the groove and a specimen can be easily stored in thegroove. Another object of the present invention is to provide a testingmember including the cover film for testing. A further object of thepresent invention is to provide a method of manufacturing the cover filmfor testing.

Means for Solving the Problems

To achieve the above objects, first, the present invention provides acover film for testing comprising: a base material; a hydrophiliccoating layer laminated on a surface of the base material; and anadhesive layer partially laminated on a surface of the hydrophiliccoating layer opposite to the base material, whereby the cover film fortesting has a region in which the adhesive layer is absent and thehydrophilic coating layer is exposed (Invention 1).

The cover film for testing according to the above invention(Invention 1) includes the adhesive layer and can thereby be well fixedto a substrate. Moreover, the cover film for testing has the region inwhich the adhesive layer is absent, and the region can thereby beoverlapped with a groove of the substrate in the plan view when atesting member is assembled. This can prevent a material thatconstitutes the adhesive layer from invading into the groove of thesubstrate. Furthermore, the cover film for testing includes thehydrophilic coating layer and has an exposed region of the hydrophiliccoating layer. A specimen can thereby be stored in the groove utilizingwettability and the specimen can easily be stored in the groove withoutusing costly and complex means. As a result of these, the use of thecover film for testing allows a testing member to be obtained with whichthe test can be well performed.

In the above invention (Invention 1), the exposed surface of thehydrophilic coating layer may preferably have a water contact angle of0° or more and 60° or less (Invention 2).

In the above invention (Invention 1, 2), the hydrophilic coating layermay preferably be composed of a material that contains at least oneselected from a siloxane-based component, a silica-based component, andan acrylic-based component (Invention 3).

In the above invention (Invention 1 to 3), the adhesive layer maypreferably comprise at least one selected from a pressure sensitiveadhesive and a thermoplastic resin (Invention 4).

In the above invention (Invention 1 to 4), the base material and thehydrophilic coating layer may preferably have transparency to light usedin a test (Invention 5).

Second, the present invention provide a testing member comprising: asubstrate having a surface provided with at least one groove; and acover film laminated on the surface of the substrate provided with thegroove, the cover film being the above cover film for testing (Invention1 to 5), the testing member being for performing an optical test for aspecimen stored in the groove (Invention 6).

In the above invention (Invention 6), in the cover film for testing, theregion in which the adhesive layer is absent may preferably overlap withthe groove of the substrate in a plan view (Invention 7).

In the above invention (Invention 6, 7), the substrate may preferablyhave transparency to light used in the test (Invention 8).

Third, the present invention provides a method of manufacturing theabove cover film for testing (Invention 1 to 5), the method comprising:a step of forming the hydrophilic coating layer on a surface of the basematerial; and a step of partially forming the adhesive layer on asurface of the hydrophilic coating layer opposite to the base material(Invention 9).

In the above invention (Invention 9), the adhesive layer may preferablybe formed by screen printing of a material on the surface of thehydrophilic coating layer opposite to the base material, wherein thematerial forms the adhesive layer (Invention 10).

Advantageous Effect of the Invention

The cover film for testing of the present invention can be well fixed toa substrate having a groove, a material that constitutes the adhesivelayer does not invade into the groove, and a specimen can be easilystored in the groove. Moreover, the cover film for testing of thepresent invention can be used to well perform the test. Furthermore,according to the method of manufacturing the cover film for testing ofthe present invention, the cover film for testing as the above can bemanufactured.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional view of a cover film for testing accordingto one or more embodiments of the present invention.

FIG. 2 is a cross-sectional view of a testing member according to one ormore embodiments of the present invention.

FIGS. 3(a) and 3(b) are respectively a plan view and a cross-sectionalview for describing the outline of a testing method according toExemplary Test 2.

FIGS. 4(a) and 4(b) are respectively a plan view and a cross-sectionalview for describing the outline of a testing method according toExemplary Test 2.

FIG. 5 is a plan view for describing the outline of a testing methodaccording to Exemplary Test 2.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

Hereinafter, one or more embodiments of the present invention will bedescribed.

<Cover Film for Testing>

FIG. 1 illustrates a cover film for testing 1 according to the presentembodiment. The cover film for testing 1 comprises a base material 10, ahydrophilic coating layer 20 laminated on a surface of the base material10, and an adhesive layer 30 partially laminated on a surface of thehydrophilic coating layer 20 opposite to the base material 10. In thecover film for testing 1, the adhesive layer 30 is partially laminatedon the surface of the hydrophilic coating layer 20 opposite to the basematerial 10 thereby to allow a region to exist in which the adhesivelayer 30 is absent and the hydrophilic coating layer 20 is exposed (thisregion may be referred to as a “hydrophilic coating layer exposed part40,” hereinafter).

The cover film for testing 1 according to the present embodiment may befor constituting a testing member used in a test and may preferably befor constituting a testing member 100 as illustrated in FIG. 2. Thetesting member 100 comprises a substrate 2 having a surface providedwith at least one or more grooves 3 and the cover film for testing 1laminated on the surface of the substrate 2 provided with the grooves 3and may be for performing an optical test for a specimen stored in thegrooves 3. As illustrated in FIG. 2, the hydrophilic coating layerexposed part 40 of the cover film for testing 1 according to the presentembodiment is provided at a position that overlaps with the grooves 3 ofthe substrate 2 in the plan view.

In the cover film for testing 1 according to the present embodiment, theadhesive layer 30 can be used to attach the cover film for testing 1 andthe substrate 2 to each other and the cover film for testing 1 cantherefore be well fixed to the substrate 2.

Moreover, in the cover film for testing 1 according to the presentembodiment, when the testing member 100 is assembled, the hydrophiliccoating layer exposed part 40 can be overlapped with the grooves 3 ofthe substrate 2 in the plan view, as previously described. In thetesting member 100 thus obtained, a material that constitutes theadhesive layer 30 does not overlap with the grooves 3 present on thesubstrate 2 in the plan view. This can avoid the above material frominvading into the grooves 3 or filling the grooves 3.

Furthermore, the cover film for testing 1 according to the presentembodiment includes the hydrophilic coating layer 20 and has thehydrophilic coating layer exposed part 40. When a specimen is stored inthe grooves 3 of the assembled testing member 100, therefore, thespecimen comes into contact with the surface of the hydrophilic coatinglayer exposed part 40 (the surface of the hydrophilic coating layer 20opposite to the base material 10). This surface is compatible with anaqueous liquid used as the specimen, and the specimen can therefore wellwet the surface and spread on the surface. This promotes the capillaryphenomenon when the specimen is stored in the grooves 3, and thespecimen readily spreads throughout the entire grooves 3. As a result,it is possible to easily store the specimen in the entire grooves 3.

As the above, the cover film for testing 1 according to the presentembodiment can be well fixed to the substrate 2, the material whichconstitutes the adhesive layer does not invade into the grooves 3 of thesubstrate 2, and the specimen can be easily stored in the entire grooves3. Thus, the cover film for testing 1 according to the presentembodiment can be used to obtain the testing member 100 with which thetest can be well performed.

In the cover film for testing 1 according to the present embodiment, thearrangement of the adhesive layer 30 and the hydrophilic coating layerexposed part 40 can be appropriately set in accordance with thepositions of the grooves 3 of the substrate 2 on which the cover filmfor testing 1 is laminated. In particular, when the cover film fortesting 1 according to the present embodiment is laminated on thesubstrate 2 as illustrated in FIG. 2, it suffices that the adhesivelayer 30 does not exist at least in a region that overlaps with thegrooves 3 in the plan view of the assembled testing member 100. That is,the location of the hydrophilic coating layer exposed part 40 may extendinto a region that does not overlap with the grooves 3 in the plan viewwhen the testing member 100 is assembled.

1. Configuration of Cover Film for Testing

(1) Base Material

In the cover film for testing 1 according to the present embodiment, theconfiguration of the base material 10 is not particularly limited,provided that the test can be performed using the testing member 100which includes the base material 10. From the viewpoint of enabling agood test, it may be preferred for the base material 10 to havetransparency to light used in the test (which may be referred to as“testing light,” hereinafter).

As a material of the base material 10, a resin film, glass, and otherappropriate material can be used, among which the resin film maypreferably be used from the viewpoint of easy production and easyhandling. Examples of the resin film include a polycarbonate film, filmsof polyester, such as polyethylene terephthalate, polybutyleneterephthalate and polyethylene naphthalate, films of polyolefin, such aspolyethylene and polypropylene, cellophane, a diacetyl cellulose film,triacetyl cellulose film, acetyl cellulose butyrate film, polyvinylchloride film, polyvinylidene chloride film, polyvinyl alcohol film,ethylene-vinyl acetate copolymer film, polystyrene film,polymethylpentene film, polysulfone film, polyether ether ketone film,polyether sulfone film, polyetherimide film, polyimide film, fluorineresin film, polyamide film, acrylic resin film, norbornene-based resinfilm, cycloolefin resin film, polyphenylene sulfide film, andliquid-crystal polymer film. These films may be in a single layer or mayalso be in a multilayer obtained by laminating two or more layers of thesame type or different types.

Among the above resin films, the polycarbonate film, polyethyleneterephthalate film, polybutylene terephthalate film, cycloolefin resinfilm, or acrylic resin film may preferably be used and the polycarbonatefilm may be particularly preferably used from the viewpoint of excellenttransparency to the testing light. Details of the testing light will bedescribed later.

The same material as that of the substrate 2 may preferably be used as amaterial of the base material 10. The use of the same material canreduce the difference in the transparency to the testing light betweenthe base material 10 and the substrate 2 and the influence of such adifference on the measurement can be reduced.

In the cover film for testing 1 according to the present embodiment, thetransmittance of the testing light through the base material 10 may bepreferably 60% or higher, particularly preferably 80% or higher, andfurther preferably 90% or higher. The above transmittance being 60% orhigher allows the cover film for testing 1 to have better transparencyto the testing light. As a result, in the testing member 100 obtainedusing the cover film for testing 1, the testing can be more accuratelyperformed. The upper limit of the above transmittance is notparticularly limited and may be 100% or lower.

In the cover film for testing 1 according to the present embodiment, thehaze value of the base material 10 may be preferably 10% or less,particularly preferably 5% or less, and further preferably 1% or less.The haze value of the base material 10 being 10% or less can effectivelyreduce the scattering of the testing light in the base material 10. Inthe testing member 100 obtained using the cover film for testing 1,therefore, the testing can be more accurately performed. The lower limitof the haze value of the base material 10 is not particularly limited,but may ordinarily be 0% or more. The haze value as used in the presentdescription refers to a value that is measured in accordance with JISK7136: 2000.

For the purpose of improving the interfacial adhesion of the basematerial 10 with the hydrophilic coating layer 20, the base material 10can be subjected to surface treatment, such as using an oxidation methodand roughening method, or primer treatment, provided that thetransparency to the testing light is not impaired. Examples of the aboveoxidation method include corona discharge treatment, plasma dischargetreatment, chromium oxidation treatment (wet type), flame treatment,hot-air treatment, ozone exposure treatment, and ultraviolet rayirradiation treatment. Examples of the roughening method include asandblast method and thermal spraying method. These surface treatmentmethods may be appropriately selected in accordance with the type of thematerial which constitutes the base material 10.

The thickness of the base material 10 may be preferably 30 μm or more,particularly preferably 50 μm or more, and further preferably 75 μm ormore. From another aspect, the thickness may be preferably 300 μm orless, particularly preferably 200 μm or less, and further preferably 150μm or less. The thickness of the base material 10 being 30 μm or moreallows the base material 10 to have sufficient strength to improve thehandling ability and it is possible to suppress the deformation andbreakage of the base material 10 when the testing member 100 is used.The thickness of the base material 10 being 300 μm or less allows thebase material 10 to readily have excellent transparency to the testinglight and the test may be well performed in the obtained testing member100.

(2) Hydrophilic Coating Layer

In the cover film for testing 1 according to the present embodiment, thematerial which constitutes the hydrophilic coating layer 20 is notparticularly limited, provided that the surface of the obtainedhydrophilic coating layer 20 has desired wettability with a specimen anddoes not adversely affect the test. The material may be preferably amaterial that includes a functional group having hydrophilicity andparticularly preferably a material that includes a large number offunctional groups having hydrophilicity on the surface.

Specific examples of the material which constitutes the hydrophiliccoating layer 20 include silicic acid-based components, silane-basedcomponents, siloxane-based components, silica-based components,acrylic-based components, elastomer-based components, phenol-basedcomponents, urea-based components, urethane-based components,melamine-based components, and cellulose-based components, among whichthe siloxane-based components, silica-based components, andacrylic-based components may be preferred from the viewpoint thatdesired wettability can be readily achieved. One type of theabove-described materials may be used alone, or two or more types mayalso be used in combination.

Examples of the above functional groups having hydrophilicity include ahydroxyl group, silanol group, carboxyl group, amino group, thiol group,aldehyde group, and quaternary ammonium group. When the material whichconstitutes the hydrophilic coating layer 20 includes such functionalgroups, hydrogen bonding may readily occur between the functional groupsand the water molecules. This can enhance the affinity between thesurface of the hydrophilic coating layer 20 and water, and desiredwettability may be readily achieved.

Examples of the above acrylic-based components include an active energyray-curable (meth)acrylic ester polymer into which a hydrophilic groupis introduced, a thermosetting (meth)acrylic ester polymer into which ahydrophilic group is introduced, and a reactive functional group monomerhaving a hydrophilic group. One type of these materials may be usedalone, or two or more types may also be used in combination. Amongthese, the active energy ray-curable (meth)acrylic ester polymer intowhich a hydrophilic group is introduced may be preferably used, and acomposition that contains the material may be particularly preferablyused, from the viewpoint that desired wettability may be readilyachieved. As used in the present description, the (meth)acrylic esterrefers to both an acrylic ester and a methacrylic ester. The sameapplies to other similar terms.

The previously-described functional groups having hydrophilicity can beused as a hydrophilic group in the active energy ray-curable(meth)acrylic ester polymer into which the hydrophilic group isintroduced. In particular, a quaternary ammonium group, hydroxyl group,carboxyl group, aldehyde group, etc. may be preferred, among which thequaternary ammonium group may be preferred. Examples of the quaternaryammonium group include a trialkylammonium group such as atrimethylammonium group, triethylammonium group, and tributylammoniumgroup. Examples of the counter ion to the nitrogen atom whichconstitutes the quaternary ammonium group include a chloride ion,bromide ion, and hydroxide ion.

In the active energy ray-curable (meth)acrylic ester polymer into whicha hydrophilic group is introduced, a functional group having activeenergy ray curability may be preferably introduced into a side chainthereby to allow the polymer to exhibit the active energy raycurability. Examples of such functional groups include a carbon-carbondouble bond.

Commercially available products may be used as the active energyray-curable (meth)acrylic ester polymer into which a hydrophilic groupis introduced. Examples of such products include product name “ACRIT8WX-030” available from Taisei Fine Chemical Co., Ltd., product name“ACRIT 8WX-018” available from Taisei Fine Chemical Co., Ltd., productname “NOSTRA H2” available from Mitsui Chemicals, Inc., product name“NOSTRA SA” available from Mitsui Chemicals, Inc., and product name“NOSTRA SA3” available from Mitsui Chemicals, Inc. Among these, theproduct name “ACRIT 8WX-030” available from Taisei Fine Chemical Co.,Ltd. may be preferably used.

When using, as the acrylic-based component, a composition that containsthe active energy ray-curable (meth)acrylic ester polymer into which ahydrophilic group is introduced, the composition may preferably furthercontain an active energy ray-curable compound from the viewpoint of moreeffectively curing the polymer. Examples of the active energyray-curable compound include, but are not limited to, polyfunctional(meth)acrylate, urethane (meth)acrylate, and polyester (meth)acrylate,among which the polyfunctional (meth)acrylate may be preferred.

Examples of the polyfunctional (meth)acrylate include dipentaerythritolhexa(meth)acrylate, ethyleneglycol di(meth)acrylate, propyleneglycoldi(meth)acrylate, butyleneglycol di(meth)acrylate, neopentylglycoldi(meth)acrylate, hexanediol di(meth)acrylate, trimethylolethanetri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritoltri(meth)acrylate, pentaerythritol tetra(meth)acrylate,dipentaerythritol penta(meth)acrylate, glycerol tri(meth)acrylate, andtriallyl (meth)acrylate. Among the above, the dipentaerythritolhexa(meth)acrylate may be preferably used.

When using, as the acrylic-based component, a composition that containsthe active energy ray-curable (meth)acrylic ester polymer into which ahydrophilic group is introduced, the composition may preferably furthercontain a photopolymerization initiator from the viewpoint of moreeffectively curing the polymer.

Examples of the photopolymerization initiator include, but are notlimited to, α-ketol-based compounds such as4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone,α-hydroxy-α,α′-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone,and 1-hydroxycyclohexyl phenyl ketone; acetophenone-based compounds suchas methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone,2,2-diethoxyacetophenone, and2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1; benzoinether-based compounds such as benzoin ethyl ether, benzoin isopropylether, and anisoin methyl ether; ketal-based compounds such as benzyldimethyl ketal; aromatic sulfonyl chloride-based compounds such as2-naphthalenesulfonyl chloride; photoactive oxime-based compounds suchas 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime;benzophenone-based compounds such as benzophenone, benzoylbenzoic acid,and 3,3′-dimethyl-4-methoxybenzophenone; thioxanthone-based compoundssuch as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone,2,4-dimethylthioxanthone, isopropylthioxanthone,2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and2,4-diisopropylthioxanthone;

camphor quinone; halogenated ketone; acylphosphinoxide; acylphosphonate;oligo(2-hydroxy-2-methyl-1-phenyl-propan-1-one); andoligo[2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone]. Amongthese, the oligo(2-hydroxy-2-methyl-1-phenyl-propane-1-one) may bepreferably used.

Examples of the above siloxane-based component include polysiloxanehaving a skeleton represented by the following formula (1).R₃SiO—(R₂SiO)n-SiR₃  (1)In the above formula (1), each R is independently thepreviously-described hydrophilic functional group or a hydrophobicfunctional group such as a hydrocarbon group (methyl group, vinyl group,alkyl group, allyl group, etc). Note, however, that a certain number ofR in the formula (1) are hydrophilic functional groups so that thepolysiloxane having the skeleton of the formula (1) has desiredhydrophilicity. In the above formula (1), n is a positive integer.

If desired, the above siloxane-based component may contain variouscommonly-used additives, such as a refractive index adjuster,antistatic, tackifier, silane coupling agent, antioxidant, ultravioletabsorber, light stabilizer, softening agent, filler, light curing agent,and photopolymerization initiator.

Commercially available products may be used as the above siloxane-basedcomponent. For example, it may be preferred to use product name “COLCOATN-103X” available from COLCOAT CO., LTD., product name “COLCOAT PS-162R”available from COLCOAT CO., LTD., product name “COLCOAT PS-169”available from COLCOAT CO., LTD., or product name “COLCOAT PX” availablefrom COLCOAT CO., LTD.

Preferred examples of the above silica-based component include those inwhich the previously-described hydrophilic functional group exists onthe surface of the crystal represented by the composition formula SiO₂.In particular, a sufficient amount of the hydrophilic functional groupsmay preferably exist on the above surface so as to exert desiredhydrophilicity.

If desired, the above silica-based component may contain variouscommonly-used additives, such as a refractive index adjuster,antistatic, tackifier, silane coupling agent, antioxidant, ultravioletabsorber, light stabilizer, softening agent, filler, light curing agent,and photopolymerization initiator.

Commercially available products may be used as the above silica-basedcomponent. For example, it may be preferred to use product name “Selfacecoat Pura PT3” available from MARUSYO SANGYO CO., LTD., “Selface coatWG-R1” available from MARUSYO SANGYO CO., LTD., or “Selface coat PuraT-type” available from MARUSYO SANGYO CO., LTD.

The thickness of the hydrophilic coating layer 20 may be preferably 1 nmor more, more preferably 10 nm or more, particularly preferably 50 nm ormore, and further preferably 100 nm or more. From another aspect, thethickness may be preferably 5,000 nm or less, particularly preferably1,550 nm or less, and further preferably 550 nm or less. When thethickness of the hydrophilic coating layer 20 is 1 nm or more, thehydrophilic coating layer 20 can readily exhibit good wettability with aspecimen, and the specimen can be more easily stored in the grooves 3 ofthe obtained testing member 100. When the thickness of the hydrophiliccoating layer 20 is 5,000 nm or less, the hydrophilic coating layer 20can readily have excellent transparency to the testing light, and goodtest can be easily performed using the obtained testing member 100.

(3) Adhesive Layer

In the cover film for testing 1 according to the present embodiment, amaterial that constitutes the adhesive layer 30 is not particularlylimited, provided that the material can well fix the cover film fortesting 1 to the substrate 2 and does not adversely affect the test.Examples of the material include a pressure sensitive adhesive,thermoplastic resin, adhesive, and self-adhesive agent. One type ofthese materials may be used alone, or two or more types may also be usedin combination.

(3-1) Pressure Sensitive Adhesive

Specific examples of the above pressure sensitive adhesive include anacrylic-based pressure sensitive adhesive, silicone-based pressuresensitive adhesive, rubber-based pressure sensitive adhesive,urethane-based pressure sensitive adhesive, polyester-based pressuresensitive adhesive, and polyvinyl ether-based pressure sensitiveadhesive, among which the acrylic-based pressure sensitive adhesive,silicone-based pressure sensitive adhesive, or rubber-based pressuresensitive adhesive may be preferred and the acrylic-based pressuresensitive adhesive may be particularly preferred from the viewpoint ofexhibiting good interfacial adhesion and from the viewpoint that thepressure sensitive adhesive is less likely to adversely affect the testusing the testing member 100. The pressure sensitive adhesive whichconstitutes the adhesive layer 30 may be active energy ray-curable ornon-active energy ray-curable.

The acrylic-based pressure sensitive adhesive is not particularlylimited, but may preferably be a non-active energy ray-curableacrylic-based pressure sensitive adhesive produced from a pressuresensitive adhesive composition P that contains a (meth)acrylic esterpolymer (A) and a crosslinker (B).

The (meth)acrylic ester polymer (A) may preferably contain a(meth)acrylic alkyl ester of which the carbon number of alkyl group is 1to 20, as the monomer which constitutes the polymer. This allows theobtained pressure sensitive adhesive to exhibit a preferred pressuresensitive adhesive property. The (meth)acrylic ester polymer (A) maypreferably contain a monomer having a reactive functional group(reactive functional group-containing monomer) as the monomer whichconstitutes the polymer. This allows the (meth)acrylic ester polymer (A)to react with the crosslinker (B) to form a crosslinked structure. The(meth)acrylic ester polymer (A) may further contain other monomers asthose which constitute the polymer.

Examples of the (meth)acrylic alkyl ester of which the carbon number ofalkyl group is 1 to 20 include methyl (meth)acrylate, ethyl(meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, n-pentyl(meth)acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,isooctyl (meth)acrylate, n-decyl (meth)acrylate, n-dodecyl(meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, andstearyl (meth)acrylate. Among these, (meth)acrylic alkyl ester of whichthe carbon number of alkyl group is 1 to 8 may be preferred from theviewpoint of further improving the pressure sensitive adhesive property,and the n-butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate may beparticularly preferred. These may each be used alone, or two or moretypes may also be used in combination.

The (meth)acrylic ester polymer (A) may preferably contain 10 mass % ormore, particularly preferably contain 15 mass % or more, and furtherpreferably contain 20 mass % or more of the (meth)acrylic alkyl ester ofwhich the carbon number of alkyl group is 1 to 20, as the monomer unitwhich constitutes the polymer. From another aspect, the (meth)acrylicester polymer (A) may preferably contain 99 mass % or less, particularlypreferably contain 98 mass % or less, and further preferably contain 97mass % or less of the (meth)acrylic alkyl ester of which the carbonnumber of alkyl group is 1 to 20, as the monomer unit which constitutesthe polymer.

Preferred examples of the above reactive functional group-containingmonomer include a monomer having a hydroxyl group in the molecule(hydroxyl group-containing monomer), a monomer having a carboxyl groupin the molecule (carboxyl group-containing monomer), and a monomerhaving an amino group in the molecule (amino group-containing monomer.One type of these reactive functional group-containing monomers may beused alone, or two or more types may also be used in combination.

Examples of the hydroxyl group-containing monomer include hydroxyalkyl(meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl(meth)acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl(meth)acrylate. Among these, the 2-hydroxyethyl (meth)acrylate may bepreferred from the viewpoint of the reactivity of hydroxyl groups withthe crosslinker (B) in the (meth)acrylic ester polymer (A) to beobtained and the copolymerizability with other monomers, 2-hydroxyethyl(meth) acrylate Is preferable. These may each be used alone, or two ormore types may also be used in combination.

Examples of the carboxyl group-containing monomer include ethylenicallyunsaturated carboxylic acids such as acrylic acid, methacrylic acid,crotonic acid, maleic acid, itaconic acid, and citraconic acid. Thesemay each be used alone, or two or more types may also be used incombination.

Examples of the amino group-containing monomer include aminoethyl(meth)acrylate and n-butylaminoethyl (meth)acrylate. These may each beused alone, or two or more types may also be used in combination.

The (meth)acrylic ester polymer (A) may preferably contain 1 mass % ormore, particularly preferably contain 2 mass % or more, and furtherpreferably contain 3 mass % or more of the reactive group-containingmonomer, as the monomer unit which constitutes the polymer. From anotheraspect, the (meth)acrylic ester polymer (A) may preferably contain 30mass % or less, more preferably contain 20 mass % or less, particularlypreferably contain 10 mass % or less, and further preferably contain 7mass % or less of the reactive group-containing monomer, as the monomerunit which constitutes the polymer.

Examples of the above other monomers include alkoxyalkyl (meth)acrylatessuch as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate;(meth)acrylates having aliphatic rings, such as cyclohexyl(meth)acrylate; non-crosslinkable acrylamides such as acrylamide andmethacrylamide; (meth)acrylates having non-crosslinkable tertiary aminogroups, such as N,N-dimethylaminoethyl (meth)acrylate andN,N-dimethylaminopropyl (meth)acrylate; vinyl acetate; and styrene.These may each be used alone, or two or more types may also be used incombination.

The polymerization form of the (meth)acrylic ester polymer (A) may be arandom copolymer or may also be a block copolymer.

The weight-average molecular weight of the (meth)acrylic ester polymer(A) may be preferably 50,000 or more, particularly preferably 100,000 ormore, and further preferably 150,000 or more. From another aspect, theweight-average molecular weight may be preferably 1,000,000 or less,particularly preferably 600,000 or less, and further preferably 300,000or less. As used in the present description, the weight-averagemolecular weight refers to a polystyrene equivalent value that ismeasured using a gel permeation chromatography (GPC) method.

One type of the (meth)acrylic ester polymer (A) may be used alone, ortwo or more types may also be used in combination.

It suffices that the above crosslinker (B) is reactive with a reactivefunctional group of the (meth)acrylic ester polymer (A). Examples of thecrosslinker (B) include an isocyanate-based crosslinker, epoxy-basedcrosslinker, amine-based crosslinker, melamine-based crosslinker,aziridine-based crosslinker, hydrazine-based crosslinker, aldehyde-basedcrosslinker, oxazoline-based crosslinker, metal alkoxide-basedcrosslinker, metal chelate-based crosslinker, metal salt-basedcrosslinker, and ammonium salt-based crosslinker. When the (meth)acrylicester polymer (A) contains a hydroxyl group as the reactive functionalgroup, it is preferred to use the isocyanate-based crosslinker among theabove crosslinkers because of excellent reactivity with hydroxyl groups.One type of the crosslinker (B) may be used alone, or two or more typesmay also be used in combination.

The isocyanate-based crosslinker contains at least a polyisocyanatecompound. Examples of the polyisocyanate compound include aromaticpolyisocyanates such as tolylene diisocyanate, diphenylmethanediisocyanate, and xylylene diisocyanate; aliphatic polyisocyanates suchas hexamethylene diisocyanate; alicyclic polyisocyanates such asisophorone diisocyanate and hydrogenated diphenylmethane diisocyanate;biuret bodies and isocyanurate bodies thereof; and adduct bodies thatare reaction products with low molecular active hydrogen-containingcompounds such as ethylene glycol, propylene glycol, neopentyl glycol,trimethylol propane, and castor oil. Among these, the hexamethylenediisocyanate may be preferred from the viewpoint of reactivity withhydroxyl groups.

The content of the crosslinker (B) in the pressure sensitive adhesivecomposition P may be preferably 0.1 mass parts or more, more preferably1 mass part or more, particularly preferable 2 mass parts or more, andfurther preferably 3 mass parts or more with respect to 100 mass partsof the (meth)acrylic ester polymer (A). From another aspect, the contentmay be preferably 20 mass parts or less, particularly preferable 15 massparts or less, and further preferably 10 mass parts or less with respectto 100 mass parts of the (meth)acrylic ester polymer (A).

The pressure sensitive adhesive composition P can be manufactured bymixing the (meth)acrylic ester polymer (A) and the crosslinker (B). Forexample, the pressure sensitive adhesive composition P can bemanufactured through preliminarily preparing the (meth)acrylic esterpolymer (A) and adding the crosslinker (B) and, if desired, otheradditives.

The (meth)acrylic ester polymer (A) can be manufactured by polymerizinga mixture of monomer units that constitute the polymer using an ordinaryradical polymerization method. Polymerization of the (meth)acrylic esterpolymer (A) can be performed by a solution polymerization method or thelike using a polymerization initiator, if desired. Examples of thepolymerization solvent include ethyl acetate, n-butyl acetate, isobutylacetate, toluene, acetone, hexane, and methyl ethyl ketone, and two ormore types may also be used in combination.

When mixing the (meth)acrylic ester polymer (A) and the crosslinker (B),they may be mixed in a diluting solvent so that a coating liquid of thepressure sensitive adhesive composition P can be prepared. Examples tobe used as the diluting solvent include aliphatic hydrocarbons such ashexane, heptane, and cyclohexane; aromatic hydrocarbons such as tolueneand xylene; halogenated hydrocarbons such as methylene chloride andethylene chloride; alcohols such as methanol, ethanol, propanol,butanol, and 1-methoxy-2-propanol; ketones such as acetone, methyl ethylketone, 2-pentanone, isophorone, and cyclohexanone; esters such as ethylacetate and butyl acetate; cellosolve-based solvents such as ethylcellosolve, among which the methyl ethyl ketone may be preferably used.

The concentration and viscosity of the coating liquid thus prepared arenot particularly limited, provided that they are within certain rangesthat allow coating, and can be appropriately selected in accordance withthe situation.

Although not particularly restricted, the silicone-based pressuresensitive adhesive may preferably contain an organopolysiloxane, inparticular, an addition-type organopolysiloxane (a cured productthereof). The addition-type organopolysiloxane may preferably beobtained through a reaction between an organohydrogenpolysiloxane and anorganopolysiloxane of which the main skeleton is a siloxane bond andwhich has an alkenyl group.

The organopolysiloxane of which the main skeleton is a siloxane bond andwhich has an alkenyl group may preferably be a compound that isrepresented by the following average unit formula (2) and has at leasttwo alkenyl groups in the molecule.R¹aSiO_((4-a)/2)  (2)(In the formula, each R¹ is independently the same or differentunsubstituted or substituted monovalent hydrocarbon group of which thecarbon number is 1 to 12 and preferably 1 to 8, and “a” is a positivenumber of 1.5 to 2.8, preferably 1.8 to 2.5, and more preferably 1.95 to2.05.)

Examples of the above unsubstituted or substituted monovalenthydrocarbon group represented by R¹ bonded to the silicon atom includealkenyl groups such as a vinyl group, allyl group, propenyl group,isopropenyl group, butenyl group, hexenyl group, cyclohexenyl group, andoctenyl group; alkyl groups such as a methyl group, ethyl group, propylgroup, isopropyl group, butyl group, isobutyl group, tert-butyl group,pentyl group, neopentyl group, hexyl group, cyclohexyl group, octylgroup, nonyl group, and decyl group; aryl groups such as a phenyl group,tolyl group, xylyl group, and naphthyl group; aralkyl groups such as abenzyl group, phenylethyl group, and phenylpropyl group; and thoseobtained by substituting a part or all of the hydrogen atoms of thesegroups with halogen atoms such as fluorine, bromine and chlorine, cyanogroups, or other appropriate groups, for example, a chloromethyl group,chloropropyl group, bromoethyl group, trifluoropropyl group, cyanoethylgroup, and the like. The alkenyl group may preferably be a vinyl groupfrom the viewpoint of reducing the curing time and increasing theproductivity.

The organohydrogenpolysiloxane has a SiH group in the molecule. Theabove alkenyl group of the organopolysiloxane and the SiH group of theorganohydrogenpolysiloxane react with each other through an additionreaction and an addition-type organopolysiloxane can thereby beobtained.

The addition-type organopolysiloxane is well cured in the presence of aplatinum catalyst and, therefore, the above silicone-based pressuresensitive adhesive may preferably contain a platinum catalyst. Examplesof the platinum catalyst include platinum black, platinum chloride,chloroplatinic acid, a reaction product of chloroplatinic acid andmonohydric alcohol, a complex of chloroplatinic acid and olefins, andplatinum bisacetoacetate.

The addition-type organopolysiloxane can contain an organopolysiloxane(silicone resin) that contains a trifunctional or tetrafunctionalsiloxane unit in the molecule in order to increase the pressuresensitive adhesive strength.

If desired, the above silicone-based pressure sensitive adhesive maycontain various commonly-used additives, such as a refractive indexadjuster, antistatic, tackifier, silane coupling agent, antioxidant,ultraviolet absorber, light stabilizer, softening agent, filler, lightcuring agent, and photopolymerization initiator.

(3-2) Thermoplastic Resin

The above thermoplastic resin is not particularly limited, provided thatthe thermoplastic resin can well fix the cover film for testing 1 andthe substrate 2 by thermal fusion bonding and does not adversely affectthe test.

Specific examples of the above thermoplastic resin include apolyester-based resin, polyolefin-based resin, polyurethane-based resin,polyester urethane-based resin, acrylic-based resin, amide-based resin,styrene-based resin, silane-based resin, and rubber-based resin. Thepolyolefin-based resin may be modified. Examples of the modifiedpolyolefin-based resin include an acid-modified polyolefin-based resinand silane-modified polyolefin-based resin. On type of them may be usedalone, or a mixture of two or more types may also be used.

The above polyester-based resin may be a hydrophobic polyester-basedresin that is soluble in an organic solvent or may also be a hydrophilicpolyester-based resin that is soluble in water or a water-solubleorganic solvent. From the viewpoint of adhesion property of the adhesivelayer 30 to the hydrophilic coating layer 20 and the substrate 2, thepolyester-based resin may preferably be a hydrophilic polyester-basedresin. Specific examples of the above polyester-based resin includepolymers obtained by condensation polymerization between at least oneselected from alcohol components such as ethylene glycol, propyleneglycol, 1,3-butanediol, 1,4-butanediol, diethylene glycol, triethyleneglycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol,cyclohexane-1,4-dimethanol, hydrogenated bisphenol A, and ethylene oxideor propylene oxide adduct of bisphenol A and at least one selected fromcarboxylic acid components such as terephthalic acid, isophthalic acid,naphthalene dicarboxylic acid, cyclohexane-1,4-dicarboxylic acid, adipicacid, azelaic acid, maleic acid, fumaric acid, and itaconic acid and anacid anhydride thereof. Among these, those corresponding to thehydrophilic polyester-based resin may preferably be used.

Examples of the polyolefin-based resin (unmodified polyolefin-basedresin) include polyethylene resins, such as very low densitypolyethylene (VLDPE, density: 880 kg/m³ or more and less than 910kg/m³), low density polyethylene (LDPE, density: 910 kg/m³ or more andless than 915 kg/m³), middle density polyethylene (MDPE, density: 915kg/m³ or more and less than 942 kg/m³), and high density polyethylene(HDPE, density: 942 kg/m³ or more), polypropylene resin (PP),ethylene-propylene copolymer, olefin-based elastomer (TPO),ethylene-vinyl acetate copolymer (EVA), ethylene-vinyl acetate-maleicanhydride copolymer, ethylene-(meth)acrylic acid copolymer,ethylene-(meth)acrylic ester copolymer, and ethylene-(meth)acrylicester-maleic anhydride copolymer. As used in the present description,the ethylene-(meth)acrylic acid copolymer refers to both anethylene-acrylic acid copolymer and an ethylene-methacrylic acidcopolymer. The same applies to other similar terms.

The thermoplastic resin may also be an ionomer in which molecules arebonded by metal cations. Examples of the ionomer include an olefin-basedionomer, urethane-based ionomer, styrene-based ionomer, andfluorine-based ionomer. One type of ionomer may be used alone, or amixture of two or more types may also be used.

Among the above specific examples of the thermoplastic resin, thepolyolefin-based resin, polyester-based resin, or acrylic-based resinmay be preferred and the polyester-based resin may be particularlypreferred from the viewpoint of exhibiting good adhesion property andfrom the viewpoint that the thermoplastic resin is less likely toadversely affect the test using the testing member 100.

The glass-transition temperature (Tg) of the thermoplastic resin whichconstitutes the adhesive layer 30 may be preferably 35° C. or higher,particularly preferably 40° C. or higher, and further preferably 45° C.or higher. From another aspect, the glass-transition temperature (Tg)may be preferably 150° C. or lower, particularly preferably 145° C. orlower, and further preferably 140° C. or lower. When the aboveglass-transition temperature (Tg) is 35° C. or higher, the adhesivelayer 30 does not readily melt even if the testing member 100 is heatedduring the test. It is therefore possible to effectively suppress theoccurrence of delamination and/or displacement at the interface betweenthe adhesive layer 30 and the hydrophilic coating layer 20 or thesubstrate 2. When the above glass-transition temperature (Tg) is 150° C.or lower, excessive heating is not necessary for the production of thetesting member 100 during the fixation of the cover film for testing 1and the substrate 2 by thermal fusion bonding of the adhesive layer 30.It is therefore possible to prevent the deformation of other members andreduce the production cost.

(3-3) Thickness of Adhesive Layer

The thickness of the adhesive layer 30 may be preferably 0.5 μm or more,particularly preferably 1 μm or more, and further preferably 1.5 μm ormore. From another aspect, the thickness may be preferably 15 μm orless, particularly preferably 5 μm or less, and further preferably 2 μmor less. When the thickness of the adhesive layer 30 is 0.5 μm or more,the cover film for testing 1 can be better fixed to the substrate 2.When the thickness of the adhesive layer 30 is 15 μm or less, theinfluence of the thickness of the adhesive layer 30 on the test can bereduced, and good test can be easily performed using the obtainedtesting member 100.

(4) Release Sheet

In the cover film for testing 1 according to the present embodiment, toprotect the adhesive layer 30 until the cover film for testing 1 islaminated on the substrate 2, a release sheet may be laminated on thesurface of the adhesive layer 30 opposite to the base material 10. Inparticular, when the adhesive layer 30 is composed of a pressuresensitive adhesive, it may be preferred to laminate a release sheet. Theshape in the plan view of the release sheet may preferably be the sameas the shape in the plan view of the base material 10, but may also bethe same as the shape in the plan view of the adhesive layer 30.

Examples to be used as the release sheet include a polyethylene film,polypropylene film, polybutene film, polybutadiene film,polymethylpentene film, polyvinyl chloride film, vinyl chloridecopolymer film, polyethylene terephthalate film, polyethylenenaphthalate film, polybutylene terephthalate film, polyurethane film,ethylene vinyl acetate film, ionomer resin film, ethylene-(meth)acrylicacid copolymer film, ethylene-(meth)acrylic ester copolymer film,polystyrene film, polycarbonate film, polyimide film, fluorine resinfilm, and liquid crystal polymer film. Crosslinked films thereof mayalso be used. Laminated films thereof may also be used.

The release surface (surface to be in contact with the adhesive layer30) of the release sheet may preferably be subjected to releasetreatment. Examples of the release agent used in the release treatmentinclude alkyd-based, silicone-based, fluorine-based, unsaturatedpolyester-based, polyolefin-based, and wax-based release agents.

The thickness of the release sheet is not particularly limited, but mayordinarily be 20 μm or more and 150 μm or less.

2. Physical Properties etc. of Cover Film for Testing

In the cover film for testing 1 according to the present embodiment, thewater contact angle on the surface of the hydrophilic coating layerexposed part 40 may be preferably 60° or less, more preferably 50° orless, particularly preferably 25° or less, and further preferably 10° orless. When the water contact angle is 60° or less, the specimen is moreeasily compatible with the surface of the hydrophilic coating layer 20,and the specimen can better wet the surface and spread on the surface.This promotes the capillary phenomenon in the testing member 100, andthe specimen readily develops throughout the grooves 3.

As a result, it is possible to more easily store the specimen in thegrooves 3. The lower limit of the above water contact angle is notparticularly limited, but may be ordinarily 0° or more, preferably 1° ormore, particularly preferably 4° or more, and further preferably 7° ormore.

In the cover film for testing 1 according to the present embodiment, thearithmetic average roughness (Ra) on the surface of the hydrophiliccoating layer exposed part 40 may be preferably 200 nm or less,particularly preferably 100 nm or less, and further preferably 50 nm orless. When the above arithmetic average roughness (Ra) is 200 nm orless, diffuse reflection of the testing light can be suppressed on thesurface of the hydrophilic coating layer exposed part 40, and the coverfilm for testing 1 may readily have transparency to the testing light.This allows the obtained testing member 100 to have improved accuracy inthe test. The lower limit of the arithmetic average roughness (Ra) isnot particularly limited, but in general may be preferably 0.1 nm ormore, particularly preferably 0.5 nm or more, and further preferably 1nm or more.

In the cover film for testing 1 according to the present embodiment, thearithmetic average roughness (Ra) on the surface of the base material 10opposite to the adhesive layer 30 may be preferably 200 nm or less,particularly preferably 100 nm or less, and further preferably 50 nm orless. When the arithmetic average roughness (Ra) is 200 nm or less,diffuse reflection of the testing light can be suppressed on the surfaceof the cover film for testing 1 at the base material 10 side when thetesting member 100 is assembled, and the cover film for testing 1 mayreadily have excellent transparency to the testing light. As a result,the obtained testing member 100 can have improved accuracy in the test.The lower limit of the above arithmetic average roughness (Ra) is notparticularly limited, but in general may be preferably 0.1 nm or more,particularly preferably 0.5 nm or more, and further preferably 1 nm ormore.

The above arithmetic average roughness (Ra) on the surface of thehydrophilic coating layer exposed part 40 and the above arithmeticaverage roughness (Ra) on the surface of the base material 10 oppositeto the adhesive layer 30 may be measured using a surface roughness meter(product name “SV-3000S4” available from Mitutoyo Corporation, stylustype) in accordance with JIS B0601: 2013.

In the cover film for testing 1 according to the present embodiment,when the hydrophilic coating layer exposed part 40 is provided in aline-like shape in the plan view, the width of the hydrophilic coatinglayer exposed part 40 (width of the line) may be preferably 20 mm orless, particularly preferably 15 mm or less, and further preferably 10mm or less. When the width is 20 mm or less, the capillary phenomenon iseffectively promoted as the specimen develops throughout the grooves 3,and the specimen can be better stored in the grooves 3. The lower limitof the above width may be preferably equal to or more than the width ofthe grooves 3 of the substrate 2 from the viewpoints of suppressing thematerial of the adhesive layer 20 from invading into the grooves 3 ofthe substrate 2 and allowing the specimen to come into good contact withthe surface of the hydrophilic coating layer exposed part 40.Specifically, the lower limit may be preferably 0.5 mm or more,particularly preferably 0.75 mm or more, and further preferably 1 mm ormore.

3. Method of Manufacturing Cover Film for Testing

The cover film for testing 1 according to the present embodiment may bepreferably manufactured by a method of manufacturing that includes astep of forming the hydrophilic coating layer 20 on a surface of thebase material 10 (this step may be referred to as a “first step,”hereinafter) and a step of partially forming the adhesive layer 30 on asurface of the hydrophilic coating layer 20 opposite to the basematerial 10 (this step may be referred to as a “second step,”hereinafter.

In the above first step, for example, the hydrophilic coating layer 20can be formed through diluting the material, which is to constitute thehydrophilic coating layer 20, with a solvent to prepare a coatingliquid, coating a surface of the base material 10 with the coatingliquid, then drying the obtained coating film and, if desired,irradiating the coating film with active energy rays.

The above solvent is not particularly limited. For example, propyleneglycol monomethyl ether, toluene, ethyl acetate, methyl ethyl ketone,etc. can be used, and it may be particularly preferred to use thepropylene glycol monomethyl ether.

The method of coating with the above coating liquid is not particularlylimited. For example, a Meyer bar method, bar-coating method,knife-coating method, roll-coating method, blade-coating method,die-coating method, gravure-coating method, etc. can be used, and it maybe particularly preferred to use the Meyer bar method.

The temperature of the above drying may be preferably 60° C. or higherand particularly preferably 70° C. or higher. From another aspect, thetemperature may be preferably 150° C. or lower and particularlypreferably 135° C. or lower. The time of drying may be preferably 5seconds or more, particularly preferably 15 seconds or more, and furtherpreferably 30 seconds or more. From another aspect, the time may bepreferably 120 seconds or less, particularly preferably 100 seconds orless, and further preferably 80 seconds or less.

Irradiation with active energy rays may be preferably performed whenusing the previously-described active energy ray-curable (meth)acrylicester polymer into which a hydrophilic group is introduced, as amaterial that constitutes the hydrophilic coating layer 20. As the aboveactive energy rays, for example, electromagnetic wave or chargedparticle radiation having an energy quantum can be used and,specifically, ultraviolet rays, electron rays or the like can be used.In particular, ultraviolet rays may be preferred because of easymanagement. Irradiation with ultraviolet rays can be performed using ahigh pressure mercury lamp, xenon lamp or the like, and the irradiancelevel of ultraviolet rays may be preferably 50 mW/cm² or more and 1,000mW/cm² or less as the illuminance. The accumulated light amount may bepreferably 50 mJ/cm² or more, particularly preferably 80 mJ/cm² or more,and further preferably 100 mJ/cm² or more. From another aspect theaccumulated light amount may be preferably 10,000 mJ/cm² or less,particularly preferably 5,000 mJ/cm² or less, and further preferably2,000 mJ/cm² or less. On the other hand, irradiation with electron rayscan be performed using an electron ray accelerator or the like, and theirradiance level of electron rays may be preferably 10 krad or more and1,000 krad or less.

In the above second step, for example, the adhesive layer 30 may bepreferably formed through diluting the material, which is to constitutethe adhesive layer 30, with a solvent to prepare a coating liquid,partially coating a surface of the hydrophilic coating layer 20 oppositeto the base material 10 with the coating liquid (including the conceptof printing), and then drying the obtained coating film. In thisoperation, the region of the surface of the hydrophilic coating layer 20to be the hydrophilic coating layer exposed part 40 (regioncorresponding to the grooves 3 of the substrate 2) is not coated withthe above coating liquid, so that the hydrophilic coating layer exposedpart 40 is formed. The above solvent and the method of coating with theabove coating liquid are not particularly limited, and the same solventand method as those when forming the hydrophilic coating layer 20 can beemployed.

In particular, the above second step may preferably includes printingthe material, which is to constitute the adhesive layer 30, on thesurface of the hydrophilic coating layer 20 opposite to the basematerial 10 thereby to partially form the adhesive layer 30. In thisprinting process, the above material is not printed on the region, inwhich the hydrophilic coating layer exposed part 40 is to be provided,of the surface of the hydrophilic coating layer 20 opposite to the basematerial 10, and the material is printed only in a region other thanthat region thereby to form the adhesive layer 30 together with thehydrophilic coating layer exposed part 40 having a predetermined shape.According to this method, the hydrophilic coating layer exposed part 40can be easily and accurately formed, and this method is excellent in thecost benefit and suitable for large-lot production. Moreover, theformation of the adhesive layer 30 by printing is easy to control thethickness of the adhesive layer 30, and the cover film for testing 1 cantherefore be manufactured with the adhesive layer 30 having a desiredthickness.

A commonly-used method can be used as the method of printing thematerial which is to constitute the adhesive layer 30. For example,screen printing, gravure printing, offset printing, ink jet printing,etc. can be used. Among the above-described printing methods, the screenprinting may be preferred from the viewpoint that the hydrophiliccoating layer 20 having a predetermined shape can be formed accurately.

When printing the material which is to constitute the adhesive layer 30,the material may be diluted with a solvent as necessary to form acoating liquid (ink), and the coating liquid may be printed. The solventcan be selected in accordance with the type of the material. Forexample, it may be preferred to use methyl ethyl ketone, toluene, ethylacetate, and the like. In particular, methyl ethyl ketone may bepreferably used.

<Testing Member>

FIG. 2 illustrates a cross-sectional view of the testing member 100according to the present embodiment. The testing member 100 comprises asubstrate 2 having a surface provided with at least one or more grooves3 and the cover film for testing 1 according to the present embodimentlaminated on the surface of the substrate 2 provided with the grooves 3.In the testing member 100, the location of the hydrophilic coating layerexposed part 40 in the cover film for testing 1 and the grooves 3 of thesubstrate 2 overlap with each other in the plan view.

The testing member 100 according to the present embodiment may be forperforming an optical test for a specimen stored in the grooves 3.

In the testing member 100 according to the present embodiment, the coverfilm for testing 1 and the substrate 2 are well fixed to each other viathe adhesive layer 30 of the cover film for testing 1. Moreover, in thetesting member 100, the adhesive layer 30 does not exist in the regionwhich overlaps with the grooves 3 in the plan view and it is therebypossible to prevent the material, which constitutes the adhesive layer30, from invading into the grooves 3 or from filling the grooves 3.Furthermore, in the testing member 100, the cover film for testing 1 hasthe hydrophilic coating layer exposed part 40 at which the hydrophiliccoating layer 20 is exposed, and the specimen stored in the grooves 3can thereby come into contact with the surface of the hydrophiliccoating layer exposed part 40, so that the specimen may readily bestored in the entire grooves 3. As the above, according to the testingmember 100 of the present embodiment, the test can be well performed.

The shape in the plan view of the testing member 100 according to thepresent embodiment is not particularly restricted, but may preferably bea disk-like shape or chip-like shape. The disk-like shape refers to aprecisely circular shape or its modified shape in the plan view of thetesting member 100. In the case of such a disk-like shape, a hole may beprovided at the center of the testing member 100. The shape of the holemay be a circular shape that is concentric in the plan view with thecircumference of the testing member 100. The chip-like shape refers to asquare shape, rectangular shape, or their modified shapes in the planview of the testing member 100.

1. Configuration of Testing Member

(1) Substrate

In the testing member 100 according to the present embodiment, thesubstrate 2 is not particularly limited, provided that the test can beperformed using the testing member 100 which includes the substrate 2.From the viewpoint of enabling a good test, it may be preferred for thesubstrate 2 to have transparency to the testing light.

As a material of the substrate 2, a resin, glass, and other appropriatematerial can be used, among which the resin may preferably be used fromthe viewpoint of easy production and easy handling. As the resin, resinsthat constitute the previously-described resin films can be used as inthe base material 10. Among such resins, polycarbonate, polyethyleneterephthalate, polybutylene terephthalate, cycloolefin resin, or acrylicresin may preferably be used and the polycarbonate may be particularlypreferably used from the viewpoint of excellent transparency to thetesting light. As previously described, the same material as that of thebase material 10 may preferably be used as a material of the substrate 2from the viewpoint of reducing the difference in the transparency to thetesting light.

In the testing member 100 according to the present embodiment, thetransmittance of the testing light through the substrate 2 may bepreferably 60% or higher, particularly preferably 80% or higher, andfurther preferably 90% or higher. The above transmittance being 60% orhigher allows the testing member 100 to have better transparency to thetesting light and the test can be more accurately performed. The upperlimit of the above transmittance is not particularly limited and may be100% or lower.

In the testing member 100 according to the present embodiment, the hazevalue of the substrate 2 may be preferably 10% or less, particularlypreferably 5% or less, and further preferably 1% or less. The haze valueof the substrate 2 being 10% or less can effectively reduce thescattering of the testing light in the substrate 2. In the testingmember 100, therefore, the test can be more accurately performed. Thelower limit of the haze value of the substrate 2 is not particularlylimited, but may ordinarily be 0% or more.

In the substrate 2, for the purpose of improving the interfacialadhesion with the adhesive layer 30, the surface of the substrate 2 onwhich the adhesive layer 30 is to be laminated can be subjected tosurface treatment, such as using an oxidation method and rougheningmethod, or primer treatment, provided that the transparency to thetesting light is not impaired. Specific examples of the above oxidationmethod and roughening method include those which are previouslydescribed as such treatment for the base material 10. These surfacetreatment methods may be appropriately selected in accordance with thetype of the material which constitutes the substrate 2.

One surface of the substrate 2 is provided with at least one or moregroove 3. In the substrate 2 of the testing member 100 illustrated inFIG. 2, the surface of the substrate 2 at the adhesive layer 30 side isprovided with a plurality of grooves 3 (three grooves 3 in FIG. 2) thateach have a width w1 and a depth d1.

The cross-sectional shape of the grooves 3 is not limited, provided thatthe grooves 3 can store a specimen and the test can be well performed.In FIG. 2, the shape of the cross section is a triangle, but is notlimited to this. In an alternative embodiment, the shape of the crosssection may be a square, rectangle, semicircle, or other appropriateshape.

The shape in the plan view of the grooves 3 is also not limited,provided that the grooves 3 can store a specimen and the test can bewell performed. For example, the shape may be a line-like shape,dot-like shape, or other appropriate shape. From the viewpoint that thetesting light can be scanned along the grooves 3, the shape maypreferably be a line-like shape. In the case of the line-like shape, theshape in the plan view of the grooves 3 may preferably be a linear shapeor a curved shape. When the testing member 100 is in thepreviously-described disk-like shape, the groove 3 may preferably bearranged in a circular shape that is concentric in the plan view withthe outer circumference of the testing member 100. In this case,scanning of the testing light for the grooves 3 can be easily performedby rotating the testing member 100 around an axis of rotation, that is,a straight line that passes through the center of the circular shape andis orthogonal to the circular shape.

Surface treatment for improving the wettability may preferably beperformed for the surface of the substrate 2 at the cover film fortesting 1 side, in particular, for portions of the surface thatconstitute the grooves 3. The testing member 100 according to thepresent embodiment has the hydrophilic coating layer exposed part 40 toallow the specimen to be readily stored in the entire grooves 3, aspreviously described. In addition to this, the above surface treatmentmay be performed for the substrate 2 thereby to allow the specimen tofurther readily develop along the grooves 3 when the specimen is storedin the grooves 3, and better storage can thus be achieved.

Examples of the above surface treatment include a method of coating theobjected surface with a component that improves the wettability and amethod of performing surface modification. Examples of the componentwhich improves the wettability include components for hydrophiliccoating.

Examples of the scheme of surface modification include corona treatment,plasma treatment, ultraviolet ray treatment, and flame treatment.

With regard to the above wettability, the surface tension on the surfaceof the substrate 2 at the cover film for testing 1 side may bepreferably 30 mN/m or more, particularly preferably 35 mN/m or more, andfurther preferably 40 mN/m or more. The surface tension being 30 mN/m ormore allows the specimen to readily wet the surfaces of grooves 3 andspread thereon when the specimen is stored in the grooves 3. Owing tosynergistic effects of such an action and the previously-describedaction that the specimen can also readily wet the surface of thehydrophilic coating layer exposed part 40 and spread thereon, thespecimen can be well stored and good test can be readily performed. Theupper limit of the surface tension is not particularly limited, but ingeneral may be preferably 70 mN/m or less, particularly preferably 65mN/m or less, and further preferably 60 mN/m or less. The surfacetension refers to a value that is measured by a wetting tension test inaccordance with JIS K6768: 1990.

In the testing member 100 according to the present embodiment,dimensions of the grooves 3 can be set in accordance with the method oftesting to be performed and the type of the specimen. For example, thewidth w1 of the grooves 3 may be preferably 50 nm or more, particularlypreferably 100 nm or more, and further preferably 150 nm or more. Fromanother aspect, the width w1 may be preferably 30 μm or less,particularly preferably 10 μm or less, and further preferably 1 μm orless. The depth d1 of the grooves 3 may be preferably 50 nm or more,particularly preferably 100 nm or more, and further preferably 150 nm ormore. From another aspect, the depth d1 may be preferably 30 μm or less,particularly preferably 10 μm or less, and further preferably 1 μm orless. The width w1 and depth d1 of the grooves 3 being within the aboveranges can sufficiently ensure the length along which the testing lighttransmits through the specimen, while suppressing the necessary amountof the specimen.

In the testing member 100 according to the present embodiment, thearithmetic average roughness (Ra) of the surface of the substrate 2opposite to the surface formed with the grooves 3 may be preferably 200nm or less, particularly preferably 100 nm or less, and furtherpreferably 50 nm or less. The arithmetic average roughness (Ra) being200 nm or less can suppress the diffuse reflection of the testing lightat the surface of the testing member 100 at the substrate 2 side and thetesting member 100 may readily have excellent transparency to thetesting light to improve the accuracy in the test. The lower limit ofthe above arithmetic average roughness (Ra) is not particularly limited,but in general may be preferably 0.1 nm or more, particularly preferably0.5 nm or more, and further preferably 1 nm or more. The abovearithmetic average roughness (Ra) may be measured using a surfaceroughness meter (product name “SV-3000S4” available from MitutoyoCorporation, stylus type) in accordance with JIS B0601: 2013.

In the testing member 100 according to the present embodiment, thethickness of the substrate 2 (the distance between the surface laminatedwith the adhesive layer 30 and the opposite surface) may be preferably0.5 mm or more, particularly preferably 0.8 mm or more, and furtherpreferably 1 mm or more. From another aspect, the thickness may bepreferably 10 mm or less, particularly preferably 5 mm or less, andfurther preferably 3 mm or less. The thickness of the substrate 2 being0.5 mm or more allows the substrate 2 to have sufficient strength and itis possible to effectively suppress the deformation of the testingmember 100 when it stores the specimen and is used for the test. Thethickness of the substrate 2 being 10 mm or less allows the testinglight to readily arrive at the specimen during the test and the test maybe accurately performed.

(2) Others

The testing member 100 according to the present embodiment may beprovided with an opening part for storing the specimen in the grooves 3.The opening part may be provided at least at one of the cover film fortesting 1 and the substrate 2, but in particular may preferably beprovided at the cover film for testing 1. With regard to the shape andsize of the opening part, the opening part may preferably be formed in ashape that is suitable for a storing means used for storing the specimenin the grooves 3. A syringe, pipette, or other appropriate instrumentmay be used as the storing means. When a syringe is used, for example,the opening part may preferably have a shape and size that allow the tipof an injection needle of the syringe to reach the grooves 3. As will beunderstood, when the testing member 100 according to the presentembodiment is provided with the above opening part, it is preferred toprovide an air-bleeding hole.

2. Method of Manufacturing Testing Member

The testing member 100 according to the present embodiment maypreferably be manufactured by attaching the surface of thepreviously-described cover film for testing at the adhesive layer 30side (when the previously-described release sheet is laminated, thesurface of the adhesive layer 30 which is exposed by removing therelease sheet) and the surface of the substrate 2 at the side formedwith the grooves 3 to each other. This attachment may be performed suchthat the grooves 3 of the substrate 2 are included in the plan view inthe hydrophilic coating layer exposed part 40 of the cover film fortesting 1.

When the adhesive layer 30 is composed of the previously-describedpressure sensitive adhesive, the testing member 100 can be manufacturedby attaching the cover film for testing 1 and the substrate 2 to eachother under an ordinary temperature. The method of attachment can becarried out by lamination, pressure bonding, or the like.

Conditions of the above lamination are not particularly limited,provided that the cover film for testing 1 and the substrate 2 can bewell fixed to each other. For example, the lamination may preferably beperformed using rollers under an ordinary temperature (e.g.room-temperature environment of 25° C.). The pressure for lamination maybe preferably 0.1 MPa or more and particularly preferably 0.5 MPa ormore. From another aspect, the pressure may be preferably 10 MPa or lessand particularly preferably 5 MPa or less. The speed of lamination maybe preferably 0.1 m/min or more and particularly preferably 0.5 m/min ormore. From another aspect, the speed of lamination may be preferably 5m/min or less and particularly preferably 1 m/min or less. When thelamination is performed under such a pressure and speed, the cover filmfor testing 1 and the substrate 2 can be well fixed to each other.

Conditions of the above pressure bonding are not particularly limited,provided that the cover film for testing 1 and the substrate 2 can bewell fixed to each other. For example, the pressure bonding maypreferably be performed using a pressing machine under an ordinarytemperature (e.g. room-temperature environment of 25° C.) The pressurefor pressure bonding may be preferably 0.1 MPa or more and particularlypreferably 0.5 MPa or more. From another aspect, the pressure may bepreferably 20 MPa or less and particularly preferably 10 MPa or less.The time of pressure bonding may be preferably 10 seconds or more andparticularly preferably 15 seconds or more. From another aspect, thetime may be preferably 60 seconds or less and particularly preferably 30seconds or less. When the pressure bonding is performed under suchconditions, the cover film for testing 1 and the substrate 2 can be wellfixed to each other in a short time.

Both the above lamination and the pressure bonding allow the attachmentunder a room temperature. The pressure bonding can therefore be readilyperformed under a temperature lower than the glass-transitiontemperature of the base material 10 and substrate 2. When the adhesivelayer 30 is composed of the previously-described pressure sensitiveadhesive, therefore, the base material 10 and the substrate 2 are lesslikely to deform due to heat, and the testing member 100 can be obtainedwith which a good test is possible.

In an embodiment, even when the adhesive layer 30 is composed of thepreviously-described pressure sensitive adhesive, the attachment of thecover film for testing 1 and the substrate 2 may be performed whileheating them. In this case, however, it may be preferred to perform theattachment under a temperature lower than the glass-transitiontemperature (Tg) of each of the cover film for testing 1 and thesubstrate 2. This can effectively suppress the deformation of the coverfilm for testing 1 and substrate 2 due to heat. In particular, when theheating is performed under a temperature lower than the glass-transitiontemperature (Tg) of the substrate 2, deformation of the grooves 3 in thesubstrate 2 can be effectively suppressed, and the test using thetesting member 100 can be better performed.

When the adhesive layer 30 is composed of the previously-describedthermoplastic resin, the cover film for testing 1 and the substrate 2may preferably be attached to each other by thermal fusion bonding ofthe thermoplastic resin. Specific scheme of the thermal fusion bondingis not limited, provided that the adhesive layer 30 in a state of beingheated to melt can be laminated on the substrate 2. For example, thislamination can be performed, such as by thermal lamination andthermocompression. In particular, the thermal lamination may preferablybe performed from the viewpoint of effectively suppressing the moltenadhesive layer 30 from invading into the grooves 3 and effectivelysuppressing the deformation of the grooves 3 due to heat and also fromthe viewpoint of simplicity.

Conditions of the thermal lamination are not particularly limited,provided that the cover film for testing 1 and the substrate 2 can bewell fixed to each other and the thermoplastic resin which constitutesthe adhesive layer 30 is suppressed from invading into the grooves 3 ofthe substrate 2. For example, the thermal lamination can be performedusing heating rollers, and the heating temperature may be preferably 60°C. or higher and particularly preferably 80° C. or higher. From anotheraspect, the heating temperature may be preferably 150° C. or lower andparticularly preferably 120° C. or lower. The pressure for laminationmay be preferably 0.1 MPa or more and particularly preferably 0.5 MPa ormore. From another aspect, the pressure may be preferably 10 MPa or lessand particularly preferably 5 MPa or less. The speed of lamination maybe preferably 0.1 m/min or more and particularly preferably 0.5 m/min ormore. From another aspect, the speed of lamination may be preferably 5m/min or less and particularly preferably 1 m/min or less. When thethermal lamination is performed under such a heating temperature,pressure, and speed, the thermoplastic resin can be effectivelysuppressed from invading into the grooves 3, and the cover film fortesting 1 and the substrate 2 can be well fixed to each other. Inparticular, the heating temperature within the above range allows thethermal lamination to be performed at a temperature that is lower thanthe glass-transition temperatures of the base material 10 and thesubstrate 2. The deformation of the base material 10 and substrate 2 dueto heat can therefore be prevented and the testing member 100 can beobtained with which a good test is possible.

Conditions of the thermocompression are not particularly limited,provided that the cover film for testing 1 and the substrate 2 can bewell fixed to each other and the thermoplastic resin which constitutesthe adhesive layer 30 is suppressed from invading into the grooves 3 ofthe substrate 2. For example, the thermocompression can be performedusing a thermal pressing machine, and the heating temperature may bepreferably 60° C. or higher and particularly preferably 70° C. orhigher. From another aspect, the heating temperature may be preferably150° C. or lower and particularly preferably 140° C. or lower. Thepressure for thermocompression may be preferably 0.1 MPa or more andparticularly preferably 0.5 MPa or more. From another aspect, thepressure may be preferably 20 MPa or less and particularly preferably 10MPa or less. The time of thermocompression may be preferably 1 minute ormore and particularly preferably 5 minutes or more. From another aspect,the time of thermocompression may be preferably 20 minutes or less andparticularly preferably 15 minutes or less. When the thermocompressionis performed under such conditions, the thermoplastic resin can beeffectively suppressed from invading into the grooves 3, and the coverfilm for testing 1 and the substrate 2 can be well fixed to each other.In particular, the heating temperature within the above range allows thethermocompression to be performed at a temperature lower than theglass-transition temperatures of the base material and the substrate 2.The deformation of the base material 10 and substrate 2 due to heat cantherefore be prevented and the testing member 100 can be obtained withwhich a good test is possible.

The method of manufacturing the substrate 2 is not particularly limited.When the substrate 2 is composed of a resin, the substrate 2 maypreferably be manufactured through molding the substrate 2, such as byinjection molding, compression molding and insertion molding and, ifnecessary, performing other processing, such as surface processing.

3. Method of Using Testing Member

The testing member 100 according to the present embodiment can be usedfor an optical test for a specimen. Specifically, after the specimen isstored in the grooves 3 of the testing member 100, the stored specimenmay be irradiated with light from outside of the testing member 100, andthe light caused by the irradiation may be measured outside the testingmember 100.

The specimen may preferably have flowability from the viewpoint that thespecimen can readily be stored in the grooves 3. Examples of thespecimen include a liquid, sol-like component, and gel-like component.In particular, the specimen may preferably be a liquid. The liquid maycontain a solid component. Specific examples of the specimen includewater as an object of a water quality test, cell extract, blood,cultured cell liquid, bacteria, archaebacteria, virus, protein, algae,and microbe.

The specimen can be stored in the grooves 3 through supplying thespecimen into the grooves 3 via the opening part provided at the testingmember 100, for example, using the previously-described storing meanssuch as a syringe and pipette. In an embodiment, a syringe or the likeprovided with an injection needle may be used to operate the injectionneedle to penetrate at a certain position of the testing member 100 andthe specimen may then be supplied into the grooves 3 via the injectionneedle.

Irradiation of the stored specimen with the testing light and thesubsequent measurement may be selected in accordance with the purpose ofthe test. For example, when measuring the concentration of a componentthat absorbs light of a certain wavelength, the absorbance at thewavelength may be measured. Specifically, the specimen is irradiatedwith the testing light which includes light of the wavelength, and theamount of light of the wavelength included in the light which transmitsthrough the specimen may then be measured. On the basis of theabsorbance thus obtained, the amount of the above component in thespecimen can be estimated. In the case of a test for the turbidity ofthe specimen, scattering light is detected which is generated when thetesting light with which the specimen is irradiated encounters particlesincluded in the specimen and, on the basis thereof, the degree ofturbidity due to the particles can be estimated. In the case of a testfor an activity state, as an index of the state of cells or blood, of afluorescent component in the specimen which contains the cells or blood,a desired test can be performed through irradiating the specimen withthe testing light which includes exciting light and measuring thefluorescence which is emitted from the fluorescent component due to theirradiation.

The type of testing light can be selected in accordance with the purposeof the test. The testing light may be, for example, laser light. In thiscase, the wavelength of the testing light may be preferably 200 nm ormore and particularly preferably 400 nm or more. From another aspect,the wavelength may be preferably 1,000 nm or less and particularlypreferably 800 nm or less. In particular, it may be preferred to use Arlaser (wavelength: 488 to 514 nm) or He—Ne laser (wavelength: 630 nm) asthe testing light.

When the testing member 100 is used, the testing member 100 may becooled or heated in accordance with the specimen to be used and the testto be performed. When the testing member 100 is heated, however, it maybe preferred to perform the heating up to a temperature lower than themelting point of each material that constitutes the testing member 100,from the viewpoint of suppressing the deformation of the testing member100 due to heat.

It should be appreciated that the embodiments heretofore explained aredescribed to facilitate understanding of the present invention and arenot described to limit the present invention. It is therefore intendedthat the elements disclosed in the above embodiments include all designchanges and equivalents to fall within the technical scope of thepresent invention.

For example, in the testing member 100, the material which constitutesthe adhesive layer 30 may be provided between the hydrophilic coatinglayer 20 and the substrate 2 in the cross section and between adjacentgrooves 3 in the plan view.

EXAMPLES

Hereinafter, the present invention will be described furtherspecifically with reference to examples, etc., but the scope of thepresent invention is not limited to these examples, etc.

<Coating Liquid C-1 for Hydrophilic Coating Layer>

A coating liquid C-1 for hydrophilic coating layer containing anacrylic-based component was prepared by uniformly mixing 50 mass parts(solid content equivalent, here and hereinafter) of dipentaerythritolhexaacrylate (available from Shin Nakamura Chemical Co., Ltd., productname “NK Ester A-DPH”), 125 mass parts of special quaternary ammoniumsalt-introduced ultraviolet ray-curable acrylate polymer (available fromTaisei Fine Chemical Co., Ltd., product name “ACRIT 8WX-030”), 5 massparts of oligo(2-hydroxy-2-methyl-1-phenyl-propane-1-one) (availablefrom Lamberti S.p.A., product name “Esacure KIP 150”), and propyleneglycol monomethyl ether as a diluting solvent. The solid contentconcentration of the coating liquid C-1 for hydrophilic coating layerwas 15 mass %.

<Coating Liquid C-2 for Hydrophilic Coating Layer>

A coating agent (available from COLCOAT CO., LTD., “COLCOAT N-103X,”solid content concentration: 2 mass %) containing a siloxane resin as asiloxane component was prepared and employed as a coating liquid C-2 forhydrophilic coating layer.

<Coating Liquid C-3 for Hydrophilic Coating Layer>

A coating agent (available from MARUSYO SANGYO CO., LTD., product name“Selface coat Pura PT3,” solid content concentration: 5 mass %)containing a silica-based component was prepared and employed as acoating liquid C-3 for hydrophilic coating layer.

<Coating Liquid P-1 for Adhesive Layer>

An acrylic ester copolymer was prepared by copolymerizing 20 mass partsof 2-ethylhexyl acrylate, 75 mass parts of butyl acrylate, and 5 massparts of 4-hydroxybutyl acrylate. The molecular weight of this acrylicester copolymer was measured by the method described later: theweight-average molecular weight (Mw) was 200,000.

A coating liquid P-1 for adhesive layer having a solid contentconcentration of 20 mass % was prepared by uniformly mixing 100 massparts of the above acrylic ester copolymer, mass parts of hexamethylenediisocyanate-based isocyanurate (available from Nippon PolyurethaneIndustry Co., Ltd., product name “CORONATE HX”) as a crosslinker, andmethyl ethyl ketone as a diluting solvent.

<Coating Liquid P-2 for Adhesive Layer>

A polyester resin (available from TOYOBO CO., LTD., Product name“Vylonal MD-1100,” thermoplastic resin, weight-average molecular weight:20,000, Tg: 40° C.) was prepared and employed as a coating liquid P-2for adhesive layer.

Here, the previously-described weight-average molecular weight (Mw)refers to a weight-average molecular weight that is measured as apolystyrene equivalent value under the following condition using gelpermeation chromatography (GPC) (GPC measurement).

<Measurement Condition>

-   -   GPC measurement apparatus: HLC-8020 available from Tosoh

Corporation

-   -   GPC columns (passing in the order below): available from Tosoh        Corporation

TSK guard column HXL-H

TSK gel GMHXL (×2)

TSK gel G2000HXL

-   -   Solvent for measurement: tetrahydrofuran    -   Measurement temperature: 40° C.

Example 1

(1) Production of Substrate

A substrate having three grooves on one surface (see the substrate 2 ofFIG. 2) was formed through injection molding of a polycarbonate resin(available from TEIJIN LIMITED, product name “Panlite AD-5503”). Thesubstrate has a disk-like shape of a diameter of 12 cm and a thicknessof 1.2 mm, and a circular hole having a diameter of 1.5 cm is providedat the center in the plan view to be concentric with the outercircumference. The three grooves are provided at an interval of 0.25 mmto be concentric with the outer circumference of the substrate in theplan view, and the width w1 and depth d1 of each groove are 200 nm. Thedistance between the groove closest to the outer circumference of thesubstrate and the outer circumference of the substrate is 2 cm. As aresult of measurement, the arithmetic average roughness (Ra) of thesurface of the substrate opposite to the surface formed with the grooveswas 120 nm, the transmittance of the testing light (wavelength: 0.63 μm)was 92%, and the haze value was 0.1%.

(2) Formation of Hydrophilic Coating Layer

The entire surface at one side of a polycarbonate film (available fromTEIJIN LIMITED, product name “PURE-ACE,” thickness: 100 μm, arithmeticaverage roughness (Ra) of surface opposite to surface to be formed withhydrophilic coating layer: 150 nm, transmittance of testing light(wavelength: 0.63 μm): 90% or more, haze value: 0.3% or less) as a basematerial was coated with the coating liquid C-1 for hydrophilic coatinglayer using a Meyer bar. The obtained coating film was dried by heatingat 70° C. for one minute and then irradiated with ultraviolet rays forcuring under the following ultraviolet irradiation condition, and ahydrophilic coating layer having a thickness of 1,500 nm was thusformed. Through this operation, a laminate comprising the base materialand the hydrophilic coating layer was obtained.

<Ultraviolet Irradiation Condition>

-   -   Ultraviolet irradiation apparatus: product name “Nitrogen purge        small conveyer-type UV irradiation apparatus CSN 2-40” available        from GS Yuasa Corporation    -   Light source: High-pressure mercury lamp    -   Lamp power: 1.4 kW    -   Conveyor speed: 1.2 m/min    -   Illuminance: 100 mW/cm²    -   Light amount: 240 mJ/cm²    -   Ultraviolet irradiation under nitrogen atmosphere (oxygen        concentration of 1% or less)        (3) Printing of Pressure Sensitive Adhesive

The above laminate was cut out into the same shape in the plan view asthat of the substrate prepared in the above process (1). Specifically,the laminate was cut out into a disk-like shape of a diameter of 12 cmwith its center provided with a circular hole of a diameter of 1.5 cmconcentric with the outer circumference.

Screen printing of the coating liquid P-1 for adhesive layer wasperformed on the surface of the cut laminate at the hydrophilic coatinglayer side. Regions to be printed on the laminate were a region outsidea circle of a diameter of 80.5 mm concentric with the outercircumference of the laminate in the plan view and a region inside acircle of a diameter of 70 mm concentric with the outer circumference ofthe laminate in the plan view. After the printing, the coating liquidP-1 for adhesive layer applied on the laminate was dried at 100° C. forone minute. Through this operation, the printed regions were formed withadhesive layers having a thickness of 3 μm, and the other region wasformed with a hydrophilic coating layer exposed part having an annularshape in the plan view. A cover film for testing was thus obtained,comprising the base material, the hydrophilic coating layer, and theadhesive layer.

(4) Production of Testing Member

Subsequently, the surface formed with the grooves of the substrateproduced in the above process (1) and the surface at the pressuresensitive adhesive layer side of the cover film for testing produced inthe above process (3) were attached to each other under the condition ofa temperature of 25° C., pressure of 0.5 MPa, and speed of 0.5 m/min.Through this attachment, the three grooves of the substrate fell withinthe hydrophilic coating layer exposed part of the cover film for testingin the plan view. A testing member was thus manufactured. The testingmember manufactured as the above was confirmed to be in a well-fixedstate.

Example 2

A testing member was manufactured in the same manner as in Example 1except that the coating liquid C-2 for hydrophilic coating layer wasused and the coating film of the coating liquid C-2 for hydrophiliccoating layer was heated at 130° C. for one minute for drying and curingthereby to form a hydrophilic coating layer having a thickness of 60 nm.The testing member thus manufactured was confirmed to be in a well-fixedstate.

Example 3

A testing member was manufactured in the same manner as in Example 1except that the coating liquid C-3 for hydrophilic coating layer wasused and the coating film of the coating liquid C-3 for hydrophiliccoating layer was heated at 130° C. for one minute for drying and curingthereby to form a hydrophilic coating layer having a thickness of 500nm. The testing member thus manufactured was confirmed to be in awell-fixed state.

Example 4

A testing member was manufactured in the same manner as in Example 1except that the coating liquid C-3 for hydrophilic coating layer wasused, the coating film of the coating liquid C-3 for hydrophilic coatinglayer was heated at 130° C. for one minute for drying and curing therebyto form a hydrophilic coating layer having a thickness of 500 nm, thecoating liquid P-2 for adhesive layer was used to form an adhesive layerhaving a thickness of 1 μm by heating at 120° C. for one minute, and thetemperature when attaching the substrate and the cover film for testingto each other was 90° C. The testing member thus manufactured wasconfirmed to be in a well-fixed state.

Comparative Example 1

A testing member was manufactured in the same manner as in Example 1except that only the base material was cut out in the same manner as inthe process (3) of Example 1 and the adhesive layer was formed in thesame manner as in the process (3) of Example 1 directly on one surfaceof the cut base material without forming a hydrophilic coating layer.The testing member thus manufactured was confirmed to be in a well-fixedstate.

Comparative Example 2

A testing member was manufactured in the same manner as in Example 1except that only the base material was cut out in the same manner as inthe process (3) of Example 1, one surface of the cut base material wassubjected to corona treatment (discharge amount: 556 W·min/m²), and theadhesive layer was formed in the same manner as in the process (3) ofExample 1 directly on the corona-treated surface without forming ahydrophilic coating layer. The testing member thus manufactured wasconfirmed to be in a well-fixed state.

Comparative Example 3

A testing member was manufactured in the same manner as in Example 1except that the entire surface at one side of the base material wascoated with the coating liquid C-2 for hydrophilic coating layer, theobtained coating film was heated at 130° C. for one minute for dryingand curing thereby to form a hydrophilic coating layer having athickness of 60 nm on the base material, a laminate thus obtained of thebase material and the hydrophilic coating layer was cut out into adisk-like shape in the same manner as in the process (3) of Example 1,and the entire surface of the cut laminate at the hydrophilic coatinglayer side was then coated with the coating liquid P-1 for adhesivelayer so as not to form a hydrophilic coating layer exposed part whenperforming screen printing of the coating liquid P-1 for adhesive layeron the surface of the cut laminate. The testing member thus manufacturedwas confirmed to be in a well-fixed state.

<Exemplary Test 1> (Measurement of Water Contact Angle)

The water contact angle on the surface of the hydrophilic coating layerexposed part of the cover film for testing manufactured in each ofExamples 1 to 4 was measured using a fully-automatic contact angle meter(“DM-701” available from Kyowa Interface Science Co., Ltd.) under thefollowing condition. For Comparative Examples 1 and 2, the water contactangle on a region with no adhesive layer of the surface of the basematerial provided with the adhesive layer was measured in the samemanner as the above. These results are listed in Table 1. This test wasnot conducted for the cover film for testing of Comparative Example 3,which is not provided with a hydrophilic coating layer exposed part anda region with no adhesive layer as the above.

-   -   Droplet volume of pure water: 2 μl    -   Measurement time: 3 seconds after dropping    -   Image analysis method: θ/2 method        <Exemplary Test 2> (Evaluation of Specimen Storage Property)

Cover films for testing were produced as test samples in the same manneras in the cover films for testing manufactured in Examples 1 to 4 andComparative Examples 1 and 2. The shape of the test samples was a shapeas described below. FIGS. 3(a) and 3(b) illustrate the outline of theshape. FIG. 3(a) is a plan view of the cover film for testing 1 as atest sample when viewed from the base material 10 side, and FIG. 3(b) isa cross-sectional view along line 3 b-3 b of the cover film for testing1 illustrated in FIG. 3(a). FIGS. 3(a) and 3(b) are presented for thecover films for testing 1 of Examples 1 to 4 and, in ComparativeExamples 1 and 2, the hydrophilic coating layer 20 in the figures isomitted. The same applies to FIGS. 4(a) and 4(b) which will be describedlater.

Specifically, in each of Examples 1 to 4, the laminate of the basematerial and the hydrophilic coating layer as previously produced wascut out into a square shape of 30 mm×30 mm in the plan view, andadhesive layers were provided so that a hydrophilic coating layerexposed part having a rectangular shape of 30 mm×2 mm in the plan viewwould exist on the surface of the laminate at the hydrophilic coatinglayer side. Here, the adhesive layers were provided so that the centerline of the base material parallel to its one side would overlap withthe center line of the hydrophilic coating layer exposed part parallelto its side of 30 mm. FIG. 3 (a) illustrates the sides having a lengthof 30 mm of the hydrophilic coating layer exposed part 40 by brokenlines. The thickness of the adhesive layers to be provided was the sameas the thickness of the adhesive layers of the cover films for testingmanufactured in Examples 1 to 4. The test samples of the cover films fortesting were thus obtained.

On the other hand, in Comparative Example 1, only the base material wascut out into a square shape in the same manner as the above, andadhesive layers were then provided in the same manner as the above toobtain a test sample of the cover film for testing. In ComparativeExample 2, only the corona-treated base material was cut out into asquare shape in the same manner as the above, and adhesive layers werethen provided in the same manner as the above to obtain a test sample ofthe cover film for testing.

Next, a polycarbonate resin (available from TEIJIN LIMITED, product name“Panlite AD-5503”) was injection-molded to produce a flat rectangularsubstrate. The length of each side in the plan view of the substrate wasmade longer than the length (30 mm) of one side of each test sampleproduced as described above.

The surface of each test sample produced as the above at the adhesivelayer side was attached to one surface of the obtained substrate. FIGS.4(a) and 4(b) illustrate a state in which the cover film for testing 1according to a test sample is attached to the substrate 2. FIG. 4 (a) isa plan view of such a state when viewed from the cover film for testing1 side, and FIG. 4(b) is a cross-sectional view along line 4 b-4 b ofthe cover film for testing 1 illustrated in FIG. 4(a). As illustrated inthese figures, the attachment was performed such that all the sides ofthe cover film for testing 1 would not overlap with any side of thesubstrate 2 in the plan view. By such attachment, a tunnel-like flowchannel 50 was formed so as to be surrounded by the hydrophilic coatinglayer exposed part 40, the substrate 2, and the side surfaces of theadhesive layers 40 and have openings at both longitudinal ends.

Then, as illustrated in FIG. 5, about 1 ml of pure water was dropped toone opening of the flow channel 50. FIG. 5 illustrates a state in whichthe cover film for testing 1 is attached to the substrate 2. Inparticular, FIG. 5 is a plan view of such a state when viewed from thecover film for testing 1 side. As illustrated in FIG. 5, the pure waterwas dropped to a position in the vicinity of one opening of the aboveflow channel 50 on the surface of the substrate 2 at the side attachedto the cover film for testing 1 so that the water droplet 4 would comeinto contact with the opening. Then, measurement was performed for thetime from when the pure water was dropped to when the pure water arrivedat the other opening after moving in the flow channel, as illustrated bythe arrow in FIG. 5, from the opening relevant to the contact toward theother opening. The measured time was used to evaluate the specimenstorage property based on the criteria below. Results are listed inTable 1.

A: Arrival of pure water at the other opening required three seconds orless after the dropping.

B: Arrival of pure water at the other opening required more than threeseconds and five seconds or less after the dropping.

C: Arrival of pure water at the other opening required more than fiveseconds and ten seconds or less after the dropping.

D: Arrival of pure water at the other opening required more than tenseconds, or the development stopped in the middle of the flow channeland pure water did not arrived at the other opening.

<Exemplary Test 3> (Evaluation of Invasion of Adhesive Layer intoGrooves)

Cross sections of grooves of the testing member manufactured in each ofthe examples and comparative examples were observed using an electronmicroscope (available from KEYENCE CORPORATION, product name “VE-9800”)and evaluation was performed in accordance with the criteria below forthe invasion into grooves of the material constituting the adhesivelayer.

o: Invasion was less than 20% of the cross sections of grooves.

x: Invasion was 20% or more of the cross sections of grooves.

TABLE 1 Temper- Presence or ature of Hydrophilic coating absence ofattachment Base layer Adhesive layer hydrophilic of substrate WaterEvaluation material Type of Type of coating layer and cover contactSpecimen of invasion Surface coating Thickness coating Thickness exposedfilm for angle storage into treatment liquid (nm) liquid (μm) parttesting (° C.) (°) property grooves Example 1 — C-1 1500 P-1 3 Present25 8.3 A ○ Example 2 — C-2 60 P-1 3 Present 25 49.0 B ○ Example 3 — C-3500 P-1 3 Present 25 16.3 A ○ Example 4 — C-3 500 P-2 1 Present 90 16.3A ○ Comparative — — — P-1 3   Present^(※1) 25 93.3 D ○ Example 1Comparative Corona — — P-1 3   Present^(※1) 25 64.2 C ○ Example 2treatment Comparative — C-1 60 P-1 3 Absent 25 — — x Example 3 ^(※1)InComparative Examples 1 and 2 without hydrophilic coating layers,presence or absence of a region with no adhesive layer on the surface ofthe base material at the adhesive layer side.

As apparent from Table 1, the testing members manufactured in theexamples are excellent in the specimen storage property, and thematerial which constitutes the adhesive layer does not invade into thegrooves.

INDUSTRIAL APPLICABILITY

The cover film for testing and the testing member according to thepresent invention are suitable for a method of optically measuring aslight amount of a specimen.

DESCRIPTION OF REFERENCE NUMERALS

-   1 . . . Cover film for testing-   10 . . . Base material-   20 . . . Hydrophilic coating layer-   30 . . . Adhesive layer-   40 . . . Hydrophilic coating layer exposed part-   100 . . . Testing member-   2 . . . Substrate-   3 . . . Groove-   4 . . . Water droplet-   50 . . . Flow channel

The invention claimed is:
 1. A testing member comprising: a substratehaving a surface provided with at least one groove extending below thesurface of the substrate and being configured to store a specimen fortesting therein, the substrate having a thickness of 0.5 mm to 10 mm andthe at least one groove having a depth of 50 nm to 30 μm; and a coverfilm laminated on the surface of the substrate provided with the atleast one groove, the cover film comprising: a base material layer; ahydrophilic coating layer laminated on an entire surface of the basematerial; and an adhesive layer laminated on a surface of thehydrophilic coating layer and extending across the entire surface of thebase layer on which the hydrophilic coating layer is laminated, whereinthe adhesive layer comprises a pressure sensitive adhesive that adheresthe cover film to the surface of the substrate without contacting the atleast one groove, and the testing member has a configuration forperforming an optical test for a specimen stored in the at least onegroove of the substrate, the configuration including the cover filmhaving a region in which the adhesive layer is absent and thehydrophilic coating layer is exposed.
 2. The cover film for testing asrecited in claim 1, wherein the exposed surface of the hydrophiliccoating layer has a water contact angle of 0° or more and 60° or less.3. The cover film for testing as recited in claim 1, wherein thehydrophilic coating layer is composed of a material that contains atleast one selected from a siloxane-based component, a silica-basedcomponent, and an acrylic-based component.
 4. The cover film for testingas recited in claim 1, wherein the base material layer and thehydrophilic coating layer have transparency to light used in a test. 5.The testing member as recited in claim 1, wherein, in the cover film fortesting, the region in which the adhesive layer is absent overlaps withthe at least one groove of the substrate in a plan view.
 6. The testingmember as recited in claim 1, wherein the substrate has transparency tolight used in the test.
 7. A method of manufacturing the cover film fortesting as recited in claim 1, the method comprising: a step of formingthe hydrophilic coating layer on the entire surface of the base materiallayer; and a step of forming the patterned adhesive layer across theentire surface of the hydrophilic coating layer and above the entiresurface of the base material layer on which the hydrophilic coated layeris laminated.
 8. The method of manufacturing the cover film for testingas recited in claim 7, wherein the patterned adhesive layer is formed byscreen printing of a material on the surface of the hydrophilic coatinglayer, wherein the material forms the adhesive layer.
 9. The testingmember as recited in claim 1, wherein the adhesive layer has a thicknessof 0.5 to 15 μm.